玉米小斑病菌O小种毒素的生物活性测定

中国玉米小斑病菌(Bipolaris maydis)小种培养滤液含有活性较强的生理活性物质,对供试15个自交系种子根生长具有明显的抑制作用;可诱导幼苗和离体叶片产生典型的小斑病症状,自交系对培养滤液致病作用的抵抗性与幼苗对病菌的致病性密切相关;O小种培养滤液对玉米根冠细胞具有强烈的致死作用,根冠细胞对培养滤液的敏感性与幼苗对病菌的感病性间存在明显的正相关。据此,初步认为O小种滤液中的生理活性物质为O毒素。

Detection of Biological Activities of the Toxin Produced by Drechslera maydis Race O in China

Filtrates produce by isolates of Bipolaris maydis race O were with high biological activities obviously Inhibited primary root growth of 15 inbred lines and also induced typical symptom of southern leaf blight on the young seedlings and in vitro leaves. The resistance of inbred lines to filtrates was closely related to the resistance to pathogen. Also,the filtrate of race O was highly acfive to cause death of corn root cap cells. There was a positive correlation with sensitivity of root cap cells to filtrates and susceptibility to the pathogen. Therefore, according to the above results,the substrate with high biological activities in filtrates of race O was considered to be race O toxin.